A novel approach to chemical bond analysis for excited states has been developed.

The laser photolysis of gold AuIII salts embedded in micelle cores of block copolymer micelles derived from polystyrene−poly-4-vinylpyridine was studied. Two types of polystyrene−poly-4-vinylpyridines having different block length have been employed, producing micelles with different properties. The influence of the type of gold salt, loading rate, presence of water, micelle characteristics, and some other parameters on the rate of reduction and gold colloid formation were investigated. The presence of water in the system containing HAuCl4·3H2O was found to accelerate the AuIII reduction, while the gold colloid size was not affected (about 3 nm). The substitution of HAuCl4·3H2O with AuCl3 results in much slower accumulation of AuI species with subsequent slower nucleation of gold colloids that results in bigger particles with mean diameter of 6.0 nm. Increasing the amount of metal compound was found to lead to an increase of the particle size.

We conducted a joint experimental−theoretical investigation of the high-pressure chemistry of europium polyhydrides at pressures of 86−130 GPa. We discovered several novel magnetic Eu superhydrides stabilized by anharmonic effects: cubic EuH 9 , hexagonal EuH 9 , and an unexpected cubic (Pm3n) clathrate phase, Eu 8 H 46 . Monte Carlo simulations indicate that cubic EuH 9 has antiferromagnetic ordering with T N of up to 24 K, whereas hexagonal EuH 9 and Pm3n-Eu 8 H 46 possess ferromagnetic ordering with T C = 137 and 336 K, respectively. The electron−phonon interaction is weak in all studied europium hydrides, and their magnetic ordering excludes s-wave superconductivity, except, perhaps, for distorted pseudohexagonal EuH 9 . The equations of state predicted within the DFT+U approach (U − J were found within linear response theory) are in close agreement with the experimental data. This work shows the great influence of the atomic radius on symmetry-breaking distortions of the crystal structures of superhydrides and on their thermodynamic stability.

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